package offer25;

public class Solution {
    static class ListNode {
        int val;
        ListNode next;
        ListNode(int x) { val = x; }
    }


    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        if(l1 == null){
            return  l2;
        }


        if(l2 == null){
            return l1;
        }

        if (l1.val < l2.val){
            l1.next = mergeTwoLists(l1.next,l2);
            return l1;
        }else{
            l2.next = mergeTwoLists(l1,l2.next);
            return l2;
        }
    }
}
